Start-stop telegraph system



Sept. 13, 1932.

E F. WATSON START- S TOP TELEGRAPH SYS TEM Filed March 25, 1951 Winn!Z'dillll INVENTO/P f. 5 WA TSCW ATTORNEY Patented Sept. 13, 1932 uiTEDSTATES EDWARD r. WATSON, or Lmcmvmanasw Yoiix, Assienon r0 annexTeresina-a I AND TELEGRAPH 'coMrnNY; A

cameraman or -"s'fonn srAn'r-s'ror TELEGRAPH SYSTEM Application filedMarch '25,

This invention relates to signaling systems and more particularly totelegraph systems embodying intermittently rotating distributors.

' An object of this invention is to decrease V the number of lineimpulses required to operate a telegraph printer at any given speed ofcharacter printing. V I v One form of start-stop telegraph system Wemploys a combination oteight impulses for the transmission of eachcharacter. Of these eight units, six are for the selection of thecharacter to be printed, one is for stopping the distributor and one isfor starting the same. The present invention employs a total of sevenimpulses. Six of these units select the desired character, While asingle additional impulse controls the starting and stopping of thereceiving, distributor. V p

A system embodying a six-unit code, in which five units are forcharacter selection, is old in the art. Such an arrangement is shown byPatent 1,57 8,299, issued March 30, 1926 to G. S. Vernann The presentinven tion, from one aspect, is an improvement-on the system of theVernam patent. v v i H In accordance with anembodiment ofthe inventiondesigned to accomplish the above and otherobjectsandto possessthe'ab'o've fig named features, a rotary distributor is a-da-pt ed to bestarted fromrest once for each revolution, upon the receipt of a signalimpulse of opposite polarity from the last signal of the precedingcombination, The distributor "1 is driven by a motor throughafrictionclutch and is restrainedfrom revolution. between successive cycles, bymeans ofa pawl-or dog; A magnet or relay is connected; to theline and Vhas an armature adapted to assume either one 2? of two positionsdepending. upon the'pol arity. of the received. impulse, forkvibrateswith the armature and the pawl is-adapted to be forced by thedistributor againstthe en'd of one of thetinesof thefork. The pawl'is "Iheld in this positionuntil a signal impulse of opposite polarityisreceived. Whenthis-hapr. pens, one tine of the fork is moved from un derthe pawhand before this tine is replaced by the otbenthe pawl movesin othe rece s? between the two tines and thus releases the- 1931. Serialnb.525,253.

ycle, Figure 1 0t the accompanyingdrawing is a yertical section of aprinting telegraph receiver embodying the present invention, the sectionbeing taken along the line 1--l of Fig. The elements are shown, initheposition .i y being. received; up I l V I Fig. 2 is aplan view of thereceiver, cer: tain parts being shown in section; o ,Fig. 3 is a sideview lookng in the direction of thearrows 83 of Fig. 2, certain partsbeing in section; I U l Fig. 4 shows certain elements of the startstopmechanism in the spacing position; Fig. 5 shows the same elements asFig.4 intermediate the spacing and marking position and V I Figs. 6 and7 show modifiedforms of the start-stop mechanism. M

The receiving magnet 2'? (Fig. 3); responds to impulses received overiatelegraph line (not shown) The nature of the signals received that eachcharacter is representedby si-X permutations of spacing and marking, im;pulses, supplemented by a singlepulse which precedes'thepermutationpulses, for control occupy while marking impulse isdistributor for revolution through another ling the starting andstoppingmechanismfor the distributing cams. In the followingjdejscription the start pulse will be referred, to asthe firstgpulse of acombination, and thesix permutation pulses as thesecond pulse to theseventhpulseinclusive: y

The start pulse for any character selected; 1

by the distant transmitter to be always of:

opposite polarity to the last permutation pulse or'the seventhpulsezof'the preceding signa-l' character. Thus, if thela'st one of 'thepermutation impulses happens to" be a 's'pacr'- ing impulse, then' t'hestart-impulse fortlie following character will bemarkin'g, and 'vice'v'er'sa. fThe transmitter at: the; distant end of; i

the teleg'raph line may'befof the enerartype disclosed in the Patent1,578,299, issuedMarch 3Q, 1926'. In case] the n'ui'nber of'perniutationimpulses is six, thetransmit ter of the Vernam patent must be, changed:correspondingly, so that there are six storing relays and segmentstherefor, instead of "which responds to the telegraph im ulsesproved-start-stop mechanism. In the'form oi invention shown in Fig. 1,there are sixcam picked up by the relay 27, will be confined chieflytothe mechanism for starting and stopping thedistri-butor. The apparatusfor iprinting the character in response to the vibrations of thearmature of relay 27 has but a remote bearing upon the presentinvention. For a description of the printing apparatus reference is madeto Morton Patent 1,745,633, issued February 4, 1930.

A distributor cam .20 issynchronized with the incoming telegraph signalsby an imparts 25, which are made of separate sheet metal stampings keyedupon asleeve 43 that is loosely mounted on the upper reduced end of ashaft 21 and'forms the driven member of a slip-friction clutch. The camparts 25 are setting devices for selector elements. The driving shaft 21is connected to a gear 23 adapted to be driven by a suitable motor (notshown). A flange 44 on sleeve '43 IS'lIl-tfposed between felt washers 45and the latter are engaged, respectively, by a collar 46 fixed to theshaft and a metal washer 47 connected to the collar by springs 48, thesprings serving to press the parts of the friction clutch into'contact.Thefriction drive device may assume any of the several forms common inthe art. r

A radial arm 49 on sleeve 43 is arranged to engage a stop 50 on anarresting dog 51. The latter is pivoted on an arm 52 (Fig. 2)

and alight spring 53 tends to move thedog toward an adjustable eccentricstop 54ron the arm. The shaft an'dfriction clutch tend to rotate'thecam-in an anti-clockwise direc tion as indicatedby the arrows in Fig. 2,and the'engagement of arm49 with stop 50 tends to rotate thedog 51 onits pivot and normally hold jthe'free end against one tine or theother'of a forked latch 55. The latch 55 is pivotally mounted on arm 52and its inner end is pressed upwardly againstthe screw.

59 by a light spring 55'. Arm 52 is mounted on a bracket 56 andisadapted to be rotated about an axis concentric with the shaft 43whereby-to orient the stop 50 with respectto the selecting mechanism(not shown).

Th inner end of the latch 55 is disposed in line withthe: axis, of thecam sleve 43 and is engaged by an adjustable screw 59 on a trip lever 60(see Figs. 1 and 3). Thelatter is pivoted with respect to bracket 56 anditsfree end is engaged by-the horizontal arm of a bell crank 61, thevertical depending arm of which engages a second bell crank 62that isoperated by an armature lever29 as shown in Fig.3.

"In Figs. 2 and 3 the armature lever 29,

bell cranks 62 and 61, triplever60,'screw- 59',"

and latch55 are shown in the positions that they occupy during the timethat the relay 2? is receiving a marking impulse. In the same figures,the position of the cam sleeve 48 and prolonged until the transmitter atthe distant end of the" line is ready to send out the next signal."WVhatever may be the particular combination representing the nextcharacter to be transmitted, it must be preceded by a spacing impulse,in order to start the distributing cam 20, for the reason that the lastpulse ofthe preceding combination happened to be a marking impulse. I'When the first or spacing impulse of th following combination arrivesit will cause the armature lever 29 to move to its spacing position.Thearmature lever in so moving rotates the bell crank 62 andconsequently the bell crank 61 which moves in a clockwise direction as,viewed inFig. 3. The movement of the bell crank lever 61 depresses thetrip lever 60, the screw 59 andthe inner end of the latch 55. Now, ifthe radial arm 49 were in motion or in someother positionwhere it 'didnotp'ress against the dog 51, the latch 55 would be free to moveto itsspacing position as shown in Fig.4. 'IIowever, the engagement of the lug50 by the radial arm 49 presses the opposite end of the dog 51 inwardlyso that the latch 55 is prevented from reaching the position shown inFig. 4. As soon as the between the upper and the lower tine of theforked latch. This rotation of the dog releases the radial arm 49 andconsequently the cam sleeve 43 togetherwith the cam 20 rotate for onerevolution.

' During thetime that the arm 49 is revolv ing from one stopposition'tothe next, the armature lever 29 responds to spacing andmarking impulses received at regular intervals but in irregular orderdepending upon the particular combinations selected at the transmittingend of the telegraph line. The spacing and marking impulses cause thelatch 55 to assume the positions shown in Fig. 4 and Fig.1,respectively, except that lug 51, does not bear against 55 except at theend of a cycle when the arm 49 bears against the lug 50. As the latch55moves from themarking position of Fig.1 to the spacing position ofFig. 4 and vice versa, the dog 51 does not move tooccupy a positionbetwenthe two tines,. except when the radial arm 49 is incits stoppedposition resting against'the lug 50 of the dog 51. w I a Wh'en'theradial arm 49 again strikes the lug 50 on the dog 51, the latch 55- willbe either in the spacing 'position*(Fig.-4) or in the Lib markingposition (Fig. 1)., dependingupon the particular character selected.Ifitherlast character selection should be a spacing impulse, the nadialarm 49 will engagethe lug 5O on the dog 51 at the time that thelatter isengagingithe lower'tine of the forked latch i as shown inFig. 4. Thelower. tine will hold the dog 51against movement until a marking impulseis received. :Upon the receipt of a marking impulse the cam sleeve43=will be released, the sequence of operation being somewhat-similar tothe sequence previously describedwhen the start impulse 'was spacing.The-marking impulse moves -the armature lever 29 to the markingposition,thereby releasing the pressure of the :bell crank '62 from thebell; crank .61, which in turn releasesiits pressure from the trip lever'60and. the screw 59, thereby permitting thespring 55'i-to rock thelatch55 in a counter-clockwise direction "toward the position shown inFig.1. The dog 51 moves into the space separating the upper and lowertines of the'latch 5.5. The move- -ment of the dog 55 is.eiiective-toarelease .the radial arm 49 for anotherrevolution in themanner previously described.

Figs. 6 and 7 are modifications of thepresentinvention. Fig. 6 is basedupon the same generalprinciple as that of the embodiment shown inFigs.1.to 5, inclusive,=butjis more simple in construction. .The cam sleeve43 and radial arm v49 of Fig.: 6 are similar in construction.and'function to the correspondthe pressure of radial arm-49 holds therighthand end down against latch 155.

The stop lever 151 carries a pin 120 which cooperates with a fork 155attached rigidly to the upper end of armature 129 of a polar relay 127.The armature and fork move to the left in response to a spacing signaland to the right when a marking signal is received. When the shaft 43reaches the limit of its travel the arm 49 will be stopped by the lever151. At this instant the pin 120 will be resting on the'top of eitherthe right hand tine or the left hand tine (as in Fig. 6), depending uponwhether the seventh impulse in a code combination happens to be spacingor marking respectively. i

W hen the armature changes its position in response to a change ofcurrent through the relay 127', the pin 120 is free to move into thespace between the two tines thereby releasing the arm 49. However, anychanges from the spacing to the marking position of the armature duringthe time that the arm combinations.

in each character.

beingunder the control ofsaid -armature," cha'racterized'bytheprov-ision of). elements ,1 49 is a in motion will-mot cause-any.rotation of the stop lever 151. I

Fig. .7; isanxinrprovemei tnpon the .device ;,shownZ-inFig. 6, theimprovement re iding-in ,;a .fork 255 .madeup of ,movablerparts. At 1the upper-eudofi armature .129'is1 a plat 119 rnally .held togetheragainst the stops 123 by a tension springlfl k. Whemth p n. -mov=es intoaxth-e space between the tines 121 12 and 122: it -wi1l rub (against theinner side of one of these'tines, which will yield in order -:to.prevent-the pin :120 :from interfering with the vibration of the.armature129, "The mod- .ilication of Fig. 7 .pQSSesses:the-further adl svantageincthat:frictionbetween the pin 1'20. .andthe: tines 121 and '122is gconsidera'blyr're duced. If desired, thepivoted tine jarrangement ofFig. 7 ymay azlsoibe applied to the forked1 1 latch 55 of Figs. l,v:2,=and v3.

WVhile the invention has been described :with reference to aselectingwode which each character is represented by permuta tions ofsix spacing :and marking: impulses, it 9 will be understood that theinvention is-not limited to any particular number of .code For example,the invention may beadapted fonuseiwith afive-unit code such asdisclosed in :the 'Vernam :Patentfi8 1,578,299, March 30, :1926; Thenecessaxriy changes ;.for adapting the machine to suit a differentnumber of code combinations will be understood by those-skilled in .theart.

- One of the .principal changes is to make thenumber: of. earns 25.equal :to the number of selecting pulses which formacombination Thepresent invention is not :to itelegraphzprinters but may be used alsoyinconnection with regenerative repeaters or other start-stop distributordevices.

What is claimedis: 1. In a communication system a -rotary distributor ofthe start-stop .type,-;a relay 131.10

liaving an armature uv-hose position isideter- -in1ned by Lthe polarityof "received impulses,

and: means for-arresting the distributor between successive cycles, saidarresting means n 5 of intercoaction between said armature. andsaidmeans whereby said arresting means is .rendered non-arresting by themovement of .1 0 said armature-from either of two positions to theother. i 1 V 2. "Ina -signaling.system,; a start-stop distributor,adapted .to-execute ,acomplete cycle of free movement,a receiving-relay,:amovg125 the starting of the distributor while the latch is at rest.

' the armature t1on;

3. Ina telegraph system, a start-stop distributor, a receiving relay, amovable latch actuated by the relay in response toreceived telegraphsignalsand having a plurality of positions of rest, stop means adaptedto'en-c gage said latch while'itis at rest in any position forpreventing the starting'of the distributor, said step means beingadapted to be released'by the latch whenever the latter is in motion .asa result of the relay moving.

4. In a signalingsystem, a rotatable member, mechanism including afriction clutch for driving said member, a stop connected to saidmember, and remote control: means for releasing said stop, said meanscomprising an armature adapted to bereciprocated by remote control, afirst arrester adapted to intercept the stop while-the armature is in'one extreme position, a second arrester adapted to intercept said stopwhile the armature is in the other extreme position, and means forreleasing the stop during the time that occupies an intermediate posl-5. In combination, a rotatable member,

driving mechanism for the member including afriction" clutch, meansfor-controlling the starting and stopping of the member, comprising astopconnected to the shaft and a reciprocating latch,. remote controlmeans for reciprocating said latch, said latch having two discretesurfaces for intercepting said stop, said surfaces being spaced apartsufli ciently to releasexthe stop duringthe interval. while the latchis'rbeingreciprocated;

6. In a start-stop signaling, system, a rotatabledistributor, means forarresting and releasing said distributor, said means comprising a stopimpelled by the'distributor, a

signal receiving magnet, a latch movable relatively to the stop byithemagnet in response to received signals, said latch having "a plurality.of spaced surfaces each adapted to mtercept the stop, said surfacesbeing separated sufficiently from each other to release the stop duringthe movement of the latch by the unagnetg; '50

1 7:. In a start stop signaling system, a re ceiving magnet PIOVlClQCl wth an armature,

a rotatable distributor, means-for arresting said: distributor, saidarresting means comprising astop for the distributor, connected thereto,a vibrating latch controlled by the receiving magnet, saidlatch havingtwo discrete surfaces, each adapted to mter- 7 March, 1931.

rter from yielding, said contactingesurfaces being separated by spacespermitting the stop toyield, andgmeans including atelegraph receivingmagnet for moving theilatch to replace one contacting surface by,another in response to a change in' polarity of the received telegraphcurrent, wherebyto-exv.pose the separatingspace tothe latchfor releasingthe distributor.

9. Inv a V telegraph. system, a receiving -relay, a vibratile'armatureactuated by the relay in responseto. received signals, a roi-tatablestart-stop distributor controlled by said armature, a stop connected tothe rotatable distributor,a latch connected to the armature andextendinglengthwise thereof, and having its free end abutting saidstop, saidlatch being adapted to ereleasesaid stop'in response to a movement ofthe armature, the latch. being yieldable transversely, whereby thevibration of the armature does not interfere. with the release of thestop.-

10. A remote control system comprising an intermittently rotatablemember, a receiving relay, a fork actuated'thereby to vibrate betweentwo extreme positionsin response toa received signal, meansfor, re-

straining said member comprising a stop adapted to be urged by saidshaft against one tine of the fork while said fork is at rest in eitherof its two extremepositions and adapted to be forced into the recessbetween the two tines when the fork changes its position, whereby torelease the member; I

11. A remote control system-as defined in, Claim 10, in which the tines.of the fork are transversely yieldable, whereby the tines may move'apartfrom each other when the stop is received between the tines. 'Intestimony whereof, I have signed my name to this specification this 23rdday-of EDWARD F. WATSON.

